ZL1 3946052 spotted today at Pomona Swap Meet

RPZ28 · #1 02-03-2004, 03:41 AM

Jason;
The way you describe your engine, I think you have a service only - 4.440 bore block, not a ZL-1.These large bore blocks can't be resleeved to a 4.250 bore. Sorry for the bad news.
Ron

**SuperNovaSS** · #2 02-03-2004, 07:40 PM

According to the machine shop it can.

Jason

RPZ28 · #3 02-04-2004, 03:45 AM

You better talk to the machine shop again. Even if they could find sleeves to fit they would be too thick to cool properly. It doesn't take much to have over heating problems with a big block.
Ron

rpoz11 · #4 02-04-2004, 04:37 AM

Jason, I dont think this is a feasable swap to use a 4.250 sleeve where a 4.440 sleeve is used...Remember the OD on the sleeve vs. yours. Your Block should be the 4.250 version.

**SuperNovaSS** · #5 02-04-2004, 04:39 AM

That is just what the machine shop told me. If it were me I'd run it this way anyway.

Jason

rpoz11 · #6 02-04-2004, 04:33 PM

This will be my last post on this. Here is where Ill ask the who's who of this BOARD as well as any others in the know: Sleeve size : does the 4.250 sleeve have a different OD than any larger displacement sleeve to be used here, 4.440 or 4.500 & larger? I am guessing now, but if a larger sleeve is installed, would the aluminum core have to be machined to accept that larger OD if this is the case?

[the last time I saw this engine setup at Pomona, it was assembled as such in your attatchment above. I never saw the sleeves being different with the heads bolted on.]

RPZ28 · #7 02-05-2004, 03:34 AM

rpoz11
You are correct, sleeve od's are different. The blocks were the same when they were casted, but as you mentioned the aluminum cores were bored out alot bigger for the 4.440 application. The 4.250 ZL-1 could only be bored saftly to 4.300. Chevrolet made these blocks from 1969 to 1972. Hope this helps.
Ron

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